EP1084601B1 - Tractor lower hitch arm side strut - Google Patents

Abstract

The side stay for the towing bar of a tractor comprises a hydraulic cylinder (9) and piston (16) and a control unit. This consists of a second cylinder (17) with an internal thread (30) at its end and a control bar (20) which can slide along it. A control lever (33) is mounted on the end of the control bar with a retaining component (36) to prevent the bar from being fully drawn out. A threaded bar (32) is adjustably mounted into the threaded bore. A second retaining component (37) is attached to the hydraulic cylinder and fixes the first retaining component to the hydraulic cylinder while allowing it to be moved along its axis. It also prevents the control bar from moving beyond the position where the piston is withdrawn as far as possible from the cylinder.

Description

The invention relates to a side strut for a lower link a tractor.

Side struts are used for the lower links of a tractor, which are laterally pivotable, at least temporarily against Stabilize a deflection or form so that when Lifting a device automatically centers the center of the device and thus the lower link in relation to the tractor longitudinal axis entry. Furthermore, the side struts serve to the Lower link on a predetermined Spreizmaß according to Category of the device to be attached in order to automatically i.e. to be able to couple from the driver's seat.

DE 197 44 328 Cl describes a side strut, to the Lower links of a tractor is used. It includes one single-acting hydraulic cylinder, a piston and a cylinder housing having. The piston rod belonging to the piston is led out end of the cylinder housing and carries first connection means for connection to corresponding connection means at the rear of the tractor.

The cylinder housing is followed axially by a hollow cylinder, in which a rod-shaped actuator is seated adjustable. This is by two spaced guide rings in the hollow cylinder and is guided by a between the guide rings arranged compression spring applied to a retracted position, in which the actuator with an end face against supports the bottom of the cylinder housing. The piston and the Actuator can be extended in opposite directions. In the case of retracted Stellelement from the hollow cylinder outstanding end of the Stellelementes is a threaded hole mounted in which a Threaded rod engages, at the second connecting means attached for connection with an associated lower link are. For the prevailing on modern tractors installation conditions is the from the series arrangement of the cylinder housing, the hollow cylinder and the setting device for the category setting with the threaded hole and the threaded rod resulting axial band length too large, so that the pendulum of the Lower link is restricted.

Furthermore, it is disadvantageous that upon actuation of the Stellelementes the once set position not secured is because, during operation, an unintentional turning of the Stellelementes can occur. This leads to a change in length.

The invention has the object of providing a side strut create, at the set by means of the threaded rod base length for a specific category or for a specific category Attachment is set as required, i. yourself does not change automatically under operating condition. Furthermore It is an object of the present invention, a side strut to propose, in the settings only in the centered position the lower link can be made.

This object is achieved according to the invention by a side strut, the one-acting hydraulic cylinder with a Piston and a cylinder housing as components, an actuating unit, a hollow cylinder with a longitudinal axis, a rod-shaped Actuator in the hollow cylinder along the longitudinal axis between a retracted position and an extended position is adjustable and has a threaded hole, the centered on the longitudinal axis and one of the hollow cylinder outstanding end face, furthermore an actuating lever, the at the protruding from the hollow cylinder end the adjusting element is mounted and further a first Retaining element, the outside of the cylinder housing removed End of the hollow cylinder is attached and on which the operating lever, a rotation of the actuating element to the hollow cylinder preventing, a relative adjustment of the same along each other the longitudinal axis, however, can be fixed allowing, a threaded rod in the threaded hole of the actuator adjustable, and a second holding element attached to a the components of the hydraulic cylinder is fixed and on the one hand the first holding member to the component undriven and along the longitudinal axis holds relatively adjustable and on the other hand at one of the fully extended position of the piston deviating position holds the actuator non-rotatably includes.

An advantage of this design is that the actuator both to the hollow cylinder and the cylinder housing or piston no rotational movement about the longitudinal axis outside the constructive intended to perform rotating games. It also ensures that an adjustment of the threaded connection, consisting from the threaded hole of the control element and the threaded rod, can only be carried out when the piston is in Relative to the cylinder is in an extended position. This position corresponds to the centered position for the Lower link, which then set in this position to each other may be required by the equipment selection Spread and, if necessary, with attached device still a game suppression achievable is.

For a first embodiment it is provided that the hollow cylinder Part of the piston of the hydraulic cylinder is. Such Training has the advantage that a very compact length for the side strut is achieved. However, it is also an arrangement possible, in which the hollow cylinder with the cylinder housing of Hydraulic cylinder centered on the longitudinal axis is connected. So there is a sequential arrangement of the same.

The first embodiment is further characterized that the second holding element attached to the cylinder housing is, wherein the first holding element along the longitudinal axis on second holding element is adjustably guided and in the direction of rotation is held non-rotatable about the longitudinal axis.

For the second embodiment it is provided that the second Holding element is fixed to the piston, wherein the first holding element adjustable along the longitudinal axis on the second holding element is guided and unadjustable in the direction of rotation about the longitudinal axis is held.

In both embodiments, the operating lever is a Axis crossing the longitudinal axis at a distance, pivoting on Actuator attached. The first holding element is fork-like designed and has a fork opening, in which the actuating lever at rest engages. This will be a rotation lock achieved, which persists even if the Piston of the single-acting hydraulic cylinder in the extended Position is located.

In this case, the second holding element also ensures that the piston or the cylinder housing to the hollow cylinder no rotational movement can perform.

For the realization of the non-rotatable mounting of the actuating element, as long as the piston of the hydraulic cylinder is not in full is in the extended position, it is provided that the actuating lever is engaged with a guide slot when the Piston in the cylinder housing one of the fully extended position assumes a different position.

To prevent rotation of the actuating element in relation to the component, to which the second retaining element is attached is provided, that the second holding element has a guide slot, the parallel to the longitudinal axis, wherein the first holding element is guided in the guide slot. This guide slot can also be used to guide the operating lever be who the lever is only in the fully extended Releases position of the hydraulic cylinder.

For the configuration of the second holding element are two given basic opportunities. It is possible, the second To make holding element as a sheet metal part. It can be this way be arranged that it is parallel to the longitudinal axis and projects axially from the cylinder housing. It is on this example fixed by screws. Alternatively, it is possible that second holding element tubular shape and to arrange so that it surrounds the hollow cylinder coaxially. It can be at the to Piston belonging piston rod be set. Alternatively it is Also, an attachment to the cylinder housing possible if the nested Arrangement according to the first embodiment is selected.

Preferred embodiments of the invention and their assignment to the lower links of a tractor are based on the drawings described in more detail.

Figur 1

eine Draufsicht auf eine schematische Darstellung der Unterlenker einer Drei-Punkt-Anbauvorrichtung eines Traktors und die Zuordnung von Seitenstreben zu diesen,

Figur 2

eine erste Ausführungsform einer erfindungsgemäßen Seitenstrebe im Längsschnitt, wobei sich der Hydraulikzylinder in der ausgefahrenen Position befindet,

Figur 3

eine Draufsicht zu Figur 2,

Figur 4

eine weitere Draufsicht, jedoch bei eingefahrener Position des Hydraulikzylinders, und

Figur 5

einen Längsschnitt durch eine weitere Ausführungsform einer Seitenstrebe.

It shows

FIG. 1

a top view of a schematic representation of the lower links of a three-point hitch of a tractor and the assignment of side struts to these,

FIG. 2

a first embodiment of a side strut according to the invention in longitudinal section, wherein the hydraulic cylinder is in the extended position,

FIG. 3

a plan view of Figure 2,

FIG. 4

another plan view, however, with the retracted position of the hydraulic cylinder, and

FIG. 5

a longitudinal section through a further embodiment of a side strut.

Figure 1 shows a plan view of two lower links 1, 1 ', which about a pivot axis 2 by means of corresponding connection means the attachment points 3, 3 'at the rear of a tractor pivot are arranged. The two attachment points 3, 3 'are with the same distance laterally offset from the tractor longitudinal axis 8. The two lower links 1, 1 'can both side and also strokes, i. Pivoting movements about the pivot axis 2 up or down, so out of the sheet level or in the leaf level and, as also apparent, for example from the dashed lines shown in solid lines drawn position laterally by the dimension S perform. For stabilization, i.e. for preventing lateral movements of the two lower links 1, 1 ', the side struts 5, 105 can be used. At the two free ends of the lower links 1, 1 'are coupling hooks 4 arranged, which recording the corresponding coupling means on a device to pull the device or in interaction with a top link, not shown, usually centered on the tractor longitudinal axis 8 above the Swivel axis 2 is arranged to wear. The two side struts 5, 105 are at one end by means of first connection means 6 laterally offset to the attachment points 3, 3 'at corresponding and on the pivot axis 2 centered fasteners the Taktorhecks set. By means of the other end of the Side struts 5, 105 provided second connection means 7 are these are each connected to a lower link 1, 1 '. The connection means 6, 7 allow a pivoting movement. It is also seen in Figure 1 that the pivot axes of the connecting means 7 with a radius R to the attachment points 3, 3 'are arranged and thus a pivoting movement with the radius R run. If the device is attached, a lateral movement S occurs on both lower links 1, 1 ', wherein a shift of the two lower links 1, 1 'of the solid lines to the dashed position takes place, it follows for the two lower links 1, 1 'starting from equal intervals L1 and L2 between the pivot axes of the articulation points 6, 7 a change such that for the lower link 1, the Dimension L1 extends to L1 'while dimension L2 shortens to L2'. The changes in length are different in size. In a pivoting of the lower links 1 and 1 'to the Attachment points 3 and 3 'in the right-pivoting sense would Accordingly, the length L1 shortened and length L2 extended. When constructing the possible shortening must be taken to ensure that, for example, the lower link 1 'in his dashed position does not strike against the rear wheels can. Furthermore, the two side struts 5, 105 serve to The attached device is centered on the tractor's longitudinal axis 8 to keep if this, for example, in the raised transport state located. The same applies even if no device is attached and the lower links 1, 1 'in transport position are located. The two side struts 5, 105 are intended in this Condition ensure that the lower links 1, 1 'are held so that they are not laterally from the set Spreizmaß A from the tractor longitudinal axis 8 outward in the direction of the Rear wheels can move. The spread dimension A between the coupling hooks 4 of the two lower links 1, 1 'can through in the side struts 5, 105 integrated telescopic adjustments made by Hand adjustable, can be adjusted when devices with one Category different from the category selected to be coupled.

From Figure 2 is a side strut 5 on an enlarged scale in To recognize relationship to Figure 1 in longitudinal section. The side strut 5 includes a single-acting hydraulic cylinder with the Cylinder housing 9 and the piston 16. The cylinder housing 9 comprises a cylinder chamber 10 at one end through a bottom is closed and at its other end a guide hole 13, which is centered on the longitudinal axis 12. Furthermore is an opening into the cylinder chamber 10 connecting bore eleventh intended. At this a pressure medium line can be connected, for example, hydraulically with the hoist of the tractor for the lower link or with a separate pressure source with interposition is connected by controls. To the cylinder housing 9, furthermore, the first connection means 6 are connected, provided for example in the form of a ball eye are. At the end remote from the first connection means 6 the guide bore 13 are a scraper 14 and a seal 15 arranged in series. In the guide hole 13, the piston 16 is slidably disposed. The piston 16 is made from a hollow cylinder 17, which at one end by a Bottom 18 is closed. The to the interior of the hollow cylinder 17 facing bottom surface of the bottom 18 is denoted by 19. To the Bottom 18 out in the outer surface of the hollow cylinder 17 a Nut mounted in which a stop ring 23 is seated, the Extending movement of the piston 16 is limited from the cylinder housing 9. In Figure 2, the piston 16 is in its maximum extended Position shown. The piston 16 is supported by the Stop ring 23 against a corresponding surface in the transition between the cylinder chamber 10 and the guide bore 13 from. By doing Hollow cylinder 17 is a rod-shaped, in particular tubular, Actuator 20 is adjustably received along the longitudinal axis 12. In Figure 2, the actuator 20 is in its retracted Position to the piston 16 and hollow cylinder 17 shown. In this case, the actuator 20 is located with its first end face 21st against the bottom surface 19. The actuator 20 is in proportion to the hollow cylinder 17 by means of two guide rings 26, 28th guided, who sit on its outer surface 24. The first guide ring 26 is close to the end of the bottom 18 of the Hollow cylinder 17 and arranged on the inner surface 25 of the hollow cylinder 17 out, as well as against a fixed in the hollow cylinder 17 Circlip 27 in Appendix, so that he is not out of the Hollow cylinder 17 can be moved out. The second guide ring 28 is located near the bottom 18 and on the outside surface 24 of the adjusting element 20 in the direction of the bottom 18 by a Circlip 29 set. The second guide ring 28 is on the inner surface 25 of the hollow cylinder 17 is guided. Between two guide rings 26, 28 are spring means in the form of a Compression spring 31 is arranged. This acts on the actuator 20 towards the bottom 18, so that this with the first end face 21 is held in contact with the bottom surface 19. The compression spring 31 is coaxial about the actuator 20 and in the hollow cylinder 17 arranged. The actuator 20 has a continuous and on the longitudinal axis 12 centered bore, wherein the outgoing from the second end face 22 of the actuating element Part designed as a threaded bore 30, in which a threaded rod 32 adjustable seats. The threaded hole 30 is in retracted state of the actuating element 20 in relation to Hollow cylinder 17 with part of its length in the hollow cylinder 17th arranged. A small part of the control element 20 protrudes in the retracted State over the bottom 18 facing away from the end of Hollow cylinder 17 axially out. At this end is a holder 35 attached to which an actuating lever 33 about the pivot axis 34 is pivotally mounted. Inactive, that's the one shown in Figure 2, the operating lever is located 33 in the fork opening 38 between two fork arms of a first Retaining element 36, the actuator 20 in relation to Piston 16 rotatably holds, so that a rotation of the actuating element 20 about the longitudinal axis 12 is not possible. The threaded rod 32 also carries the second connection means 7. These serve for attachment to a lower link. By the nested ones Construction, an extremely short installation length is achieved.

The following are the means for rotation of the control element 20 described in more detail with reference to Figures 2 to 4. The first Retaining element 36 is fork-shaped, so that there is a fork opening 38 between the fork arms results in the operating lever 33 after pivoting about the pivot axis 34 in the direction on the outer circumference of the cylinder housing 9 and der Hohlzylinders 17 to intervene. The actuator 20 is then in proportion to the hollow cylinder 17, on which the first holding element 36 is attached, held undrotatable. In addition, a second Holding element 37 is provided, which is designed as a sheet metal part and by means of screws on the first connection means 6 removed End of the cylinder housing 9 is fixed and from this end projects in the direction of the second connection means 7. It points one outgoing from the cylinder housing 9 end Guide slot 39, in which the first holding member 36 constantly is guided. It leads in this guide slot 39 a relative movement to the second holding member 37, when the piston 16 in the cylinder housing 9 on or extended from this.

In Figures 2 and 3, the piston 16 is in its out of the cylinder housing 9 fully extended position shown, so that the operating lever 33 free to pivot about the pivot axis 34 upwards in right-waving sense is movable. With the upturned Operating lever 33, which leave the guide slot 39 has, the actuator 20 can be rotated about the longitudinal axis 12 be so that depending on the direction of rotation, the threaded rod 32nd from the actuator 20 extends or retracts. This changes the longitudinal distance between the connecting means 6,7 of the side strut 5. Is carried out in the illustrated in Figures 2 and 3 pivoted, i. inactive position or rest position of the actuating lever 33, a retraction of the piston 16 in the cylinder housing 9, for example, to the position as shown in FIG 4, the operating lever 33 is immersed so far in the guide slot 39 that he even if he swung is, not to a rotational adjustment of the control element 20 can be used. This also creates a security insofar as a category setting or game setting attached device can only be done when the Lower links are in the centered position.

FIG. 5 shows a further embodiment of a side strut 105, in relation to the embodiment according to FIGS 2 to 5 have been selected for similar components reference numerals, the to those of the first embodiment are increased by the number 100. In this respect, reference is made to their description for that for the figure 2. However, the following are the main differences described.

In the side strut 105 according to the second embodiment are the first connection means 6 via the piston rod 40 directly with connected to the piston 116. The cylinder housing 109 is fixed with the hollow cylinder 117 connected. This closes axially the longitudinal axis 112 centered on the cylinder housing 109 at. In this is, as described in connection with Figures 2 to 4, the actuator 120 by means of the guide rings 126th and 128 against the force of a compression spring 131 from a retracted one Position in which the first end face 121 against the Cylinder housing 109 adjacent bottom surface 119 abuts, to a extended position displaced. In the from the hollow cylinder 117 projecting portion of the actuating element 120 is starting from the second end face 122 a threaded bore 130 attached, in which the threaded rod 132, the second Connecting means 7 carries, seated adjustable.

The actuating lever 133 is also via a holder 135 at attached to the actuator 120 and at this about a pivot axis 134 held pivotally. The hollow cylinder 117 is connected to the provided first retaining element 136, as in connection with is configured described in Figures 2 to 4. In Figure 5 is the actuating lever 133 is drawn in the rest position. Of Further, the piston 116 is in the fully extended Position. The second holding element 137 is tubular and arranged coaxially with the hollow cylinder 117 and cylinder housing 109. It is fixed to the piston rod 40. It rejects his the second terminal means 7 near end starting one Guide slot 139, which is parallel to the longitudinal axis 112 and, as described in connection with FIGS. 2 to 4, on the one hand, the first holding element 136 along the Longitudinal axis 112 receives relatively adjustable, but this in the direction of rotation keeps unrotatable. The piston 116 moves into the cylinder housing 109, the operating lever 133 also dips into the Guide slot 139 and a length adjustment by means of Threaded rod 132 and the threaded hole 130 is no longer possible. The guide slot 139 holds namely the operating lever 133 even if this from the rest position to an operating position is pivoted so that the actuator 120th is non-rotatable.

Since usually the stroke of the piston of the hydraulic cylinder also essentially the adjustment of the control element in Hollow cylinder corresponds, the actuator is then also non-rotatable held when it is against the force of the compression spring out of the Hollow cylinder extends. This applies to both embodiments.

LIST OF REFERENCE NUMBERS

1, 1 '

lower link

2

swivel axis

3, 3 '

fastening point

4

coupling hook

5, 105

side strut

6

first connection means

7

second connection means

8th

tractor longitudinal axis

9, 109

cylinder housing

10, 110

cylinder space

11

connecting bore

12, 112

longitudinal axis

13

guide bore

14

scraper

15

poetry

16, 116

piston

17, 117

hollow cylinder

18

ground

19, 119

floor area

20, 120

actuator

21, 121

first end face

22, 122

second end face

23

stop ring

24, 124

Outer surface of the actuating element

25, 125

palm

26, 126

first guide ring

27

circlip

28, 128

second guide ring

29, 129

circlip

30, 130

threaded hole

31, 131

compression spring

32, 132

threaded rod

33, 133

actuating lever

34, 134

swivel axis

35, 135

holder

36, 136

first holding element

37, 137

second holding element

38

fork opening

39, 139

guide slot

40

piston rod

A

of spread

L1, L2, L1 ', L2'

length

R

radius

S

lateral movement

Claims (10)

1. Side strut (15, 105) for a lower steering arm (1, 1') of a tractor, comprising

   a single-action hydraulic cylinder, having a piston (16, 116) and a cylinder housing (9, 109) as components,

   a setting unit,
   having a hollow cylinder (17, 117) with a longitudinal axis (12, 112), a rod-shaped setting element (20, 120), movable in the hollow cylinder (17, 117) along the longitudinal axis (12, 112) between a moved-in and a moved-out position and which setting element (20, 120) having a threaded bore (30, 130), centred on the longitudinal axis (12, 112) and starting from a second end face (22, 122) projecting from the hollow cylinder (17, 117), and further with an actuating lever (33, 133) attached to the end of the setting element (20, 120) projecting from the hollow cylinder (17, 117), and furthermore with a first holding element (36, 136) attached on the outside to the end of the hollow cylinder (17, 117) removed from the cylinder housing (17, 117) and on which the actuating lever (33, 133) is retainable in such a way, that a rotation of the setting element (20, 120) relative to the hollow cylinder (17, 117) is prevented and that a relative displacement of the same towards each other along the longitudinal axis (12, 112) is possible,

   a threaded rod (32, 132), inserted into the threaded bore (30, 130) of the setting element (20, 120) in an adjustable manner, and

   a second holding element (37, 137), attached to one of the components (16, 116, 9, 109) of the hydraulic cylinder and holding on the one hand the first holding element (36, 136) in a non-rotatable manner to the component and adjustable along the longitudinal axis (12, 112) relative thereto and on the other hand in a position deviating from the completely moved-out position of the piston (16, 116) holding the setting element (20, 120) in a non-rotatable manner.
2. Side strut according to claim 1,
   characterised in that
   the hollow cylinder (17) is part of the piston (16) of the hydraulic cylinder.
3. Side strut according to claim 1,
   characterised in that
   the hollow cylinder (117) is connected to the cylinder housing (109) of the hydraulic cylinder.
4. Side strut according to claims 1 and 2,
   characterised in that
   the second holding element (37) is attached to the cylinder housing (9), wherein the first holding element (36) is guided adjustably along the longitudinal axis (12) on the second holding element and is held non-rotatably in rotational direction around the longitudinal axis (12).
5. Side strut according to the claims 1 and 3,
   characterised in that
   the second holding element (137) is attached to the piston (116), wherein the first holding element (136) is guided adjustably along the longitudinal axis (112) on the second holding element (137) and is held non-rotatably in rotational direction around the longitudinal axis (112).
6. Side strut according to claim 1,
   characterised in that
   the actuating lever (33, 133) is attached to the setting element (20, 120) pivotably around a pivot axis (34, 134), intersecting at a right angle the longitudinal axis (12, 112) with a distance in-between, and that the first holding element (36, 136) is formed yoke-like and has a yoke opening, into which the actuating lever (33, 133) in the resting condition engages.
7. Side strut according to one of claims 4 or 5,
   characterised in that
   the actuating lever (33, 133) engages in a guiding slot (39), when the piston (16, 116) takes up a position in the cylinder housing (9, 109) , deviating from the fully moved-out position.
8. Side strut according to one of claims 4 or 5,
   characterised in that
   the second holding element (37, 137) has a guiding slot (39, 139), extending parallel to the longitudinal axis (12, 112), wherein the first holding element (36, 136) is guided in the guiding slot (39, 139).
9. Side strut according to one of claims 4 or 5,
   characterised in that
   the second holding element (37) is formed as a plate metal part, arranged parallel to the longitudinal axis (12) and projecting axially from the cylinder housing (9).
10. Side strut according to one of claims 4 or 5,
    characterised in that
    the second holding element (137) is formed tubular in shape and surrounds coaxially the hollow cylinder (117).

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